Exam Review Questions - Multiple Choice The following questions are for review. They are in no particular order. 1. An atom of iron 56 26Fe has... a) 26 protons, 26 electrons, 30 neutrons b) 30 protons, 30 electrons, 26 neutrons c) 26 protons, 26 electrons, 56 neutrons d) 30 protons, 26 electrons, 26 neutrons 2. A bromide ion will have a charge of... a) -1 b) -2 c) -3 d) +1 3. The atom with an atomic number 13 will tend to... a) gain 5 electrons b) gain 3 electrons c) lose 5 electrons d) lose 3 electrons 4. The first four ionization energies of an element X are 740, 1450, 7730, and 10 470 kj mol -1. The formula for the stable ion of X is most likely to be... a) X + b) X 2+ c) X 3+ d) X 4+ 5.Which one of the following best supports the concept that electrons in atoms may have only certain energies (i.e. are quantized )... a) emission spectrum of mercury b) mass spectrum of the isotopes c) scattering of alpha particles by gold foil d) make up of the periodic table 6. For the species below, the one that would be expected to require the most energy for the removal of another electron is... a) Na + b) Mg + c) Al 2+ d) Cl + 7. discovered the nuclear atom... a) Thomson b) Bohr c)rutherford d) Ms. Pall 8. How many electrons are in the outer (highest) energy level of a 39 19K +1 ion? a) 3 b) 5 c) 7 d) 8 9. The following species Cl -, Ar, and K + all have the same... a) number of protons b) number of electrons c) number of neutrons d) number of isotopes 10. Which of the following elements would have the largest atomic radius... a) Li b) Cs c) F d) I 1
11. All of the following ions are isoelectronic with a Noble gas except... a) Al 3+ b) H - c) Ga 3+ d) Cl - 12. Of the pairs of elements below, which would have the highest melting point? a) MgCl 2 b) NaCl c) CCl 4 d) NCl 3 13. Which of the following molecule has only Van-der-Walls forces of attraction... a) HF b) CF 4 c) NaF d) NF 3 14. The formula for a compound of thulium is TmPO 4. The formula for the nitrate of thulium would be... a) Tm(NO 3 ) 3 b) Tm N c) Tm 2 (NO 3 ) 3 d) (NO 3 ) 3 Tm 15. Which of the following molecule would be polar and pyramidal... a) CHCl 3 b) NI 3 c) OF 2 d) BeCl 2 16. Atoms of the different isotopes of the same element are identical in the... a) number of electrons b) sum of number of protons and neutrons c) sum of the number of protons and neutrons d) mass number 17. All of the following are isoelectronic ( have the same number of valence electrons) except... a) CO 3 2- b) NO 3 - c) SO 3 2- d) BO 3 3-18. What is the basis of metallic bonding? a) the attraction of metal ions for delocalized electrons b) the attraction between neutral metal ions c) the attraction of oppositely charged ions d) the sharing of two valence electrons between two atoms 19. When is ionic bonding likely to occur between two atoms? a) when both atoms have low ionization energy and low electron affinity b) when both atoms have high ionization energy and low electron affinity c) when both atoms have high ionization energy and high electron affinity d) when one atom has high ionization energy and high electron affinity, and the other atom has low ionization energy and low electron affinity. 20. Which of the liquid substances listed below has polar molecules, predominantly covalent bonding between atoms of the molecule and a significant degree of hydrogen bonding between molecules? a) liquid hydrogen, H 2 b) liquid sodium chloride, NaCl c) liquid silane, SiH 4 d) liquid hydrogen fluoride, HF 2
21. Which of the three following molecules will be polar? H 2 O PF 3 CH 4 a) H 2 O and CH 4 b) H 2 O and PF 3 c) all of them d) none of them 22. Which one of the following elements has the highest first ionization energy? a) Na b) Fe c) Cl d) I 23. In which group of the periodic table are you likely to find a metalloid? a) the alkali metal family b) the alkaline earth family c) the carbon family d) the halogen family 24. Which atom has the smallest radius? a) K b) Ga c) Br d) Rb 25. A certain element is listed as having atomic mass of 72.6 u. It is probably true that it contains... a) a mixture of isomers b) a mixture of allotropes c) a mixture of isotopes d) an impurity 26. In which of the following solids are all the atoms held together by covalent bonds? a) silicon dioxide b) sodium chloride c) iodine d) potassium nitrate 27. The number of valence electrons in sulphur trioxide, SO 3, is... a) 18 b) 24 c) 32 d) 40 28. Which elements are characterized by the filling of d orbitals? a) Halogens b) Rare earths c) Actinides d) 1 st Transition series 29. The chemical family that readily forms anions is the... a) alkali metals b) alkaline earths c) transition elements d) halogens 30. When an electron in an atom moves from an excited state to a ground state... a) it produces a continuous spectrum b) it produces a discontinuous spectrum c) it produces an absorption spectrum d) it produces a magnetic resonance spectrum 31. Which one of the following will be observed as the atomic number of the elements in a single group of elements on the periodic table increases? a) an increase in the atomic radii b) an increase in the ionisation energies c) an increase in the electronegativities d) a decrease in the ionic radii 3
32. Hydrogen, HF, has a boiling point of 20 0 C, while hydrogen chloride, HCl, has a boiling point of - 84 0 C This is explained by... a) the Van der Waals forces b) the hydrogen bonds c) the orbital structure d) the molecular structure 33. Given a list of the following substances: CH 4, Ne, C 2 H 5 OH, CO 2 Which of these is molecular and bonded by hydrogen bonds? a) CH 4 b) Ne c) C 2 H 5 OH d) CO 2 34. Given the following substances : CaF 2, HF, F 2, CH 3 Cl Which substance would you expect to have the highest melting point? a) CaF 2 b) HF c) F 2 d) CH 3 Cl 35. The elements X and Y have 6 and7 electrons respectively, in the highest energy levels of their atoms. What is the formula and type of bonding used in a compound formed by these elements? a) XY 2, ionic b) X 2 Y, ionic c) X 2 Y, covalent d) XY 2, covalent 36. An element, J, has three isotopes with the relative abundances of... Atomic Number Atomic Mass Relative Abundance 22 45.00 10 % 22 46.00 75 % 22 47.00 15 % Given this information, what is the atomic mass of element J? a) 22.00 u b) 46.00 u c) 46.05 u d) 47.90 u 37. Which statement is true about ionization energies? a) The first ionization energies in a period increase smoothly from left to right across the periodic table. b) The first ionization energies of the elements in a family increase smoothly down the family. c) Successive ionization energies increase smoothly with the charge on the species. d) Successive ionization energies increase with the charge on the species in an irregular manner. 38. In which one of the species below would the F - X - F bond angle be expected to be the smallest? a) CF 4 b) NF 3 c) BF 3 d) OF 2 4
39. The increase in boiling points observed for F 2, Cl 2, Br 2, I 2 is best attributed to... a) an increase in Van der Waals forces with increasing atomic number. b) a decrease in the electronegativity with increasing atomic number. c) an increase in the X - X bond energy with increasing atomic number. d) a decrease in the ionization energy with increasing atomic number. 40. Which of the following substances would be expected to exhibit hydrogen bonding? I. CH 3 F II. CH 3 OH III. CH 3 NH 2 a) I only b) II only c) II and III only d) I, II and III 41. Which one of the following species would be expected to have the largest radius? a) Sr b) Sr 2+ c) Te d) I 42. Magnesium is found in the second column of the periodic table. What ionic state and charged particles will it have after reacting with another atom in an ionic bond? a) Mg 2+, 10 protons, 12 electrons b) Mg 2+, 12 protons, 10 electrons c) Mg +, 12 protons, 10 electrons d) Mg 2-, 12 protons, 14 electrons 43. Which of the following particles is isoelectronic with an atom of argon? a) K - b) Cl + c) Na + d) S 2-44. Which one of the following electronic configurations is correct for a halogen atom? a) [Ne] 3s 2 3d 5 b) [Ar] 4s 2 4p 5 c) [Ar] 4s 2 3d 5 d) [Kr] 5s 2 4d 10 5p 5 45. What is the systematic, IUPAC, name for the compound Cr 2 O 3? a) Chromium (III) oxide b) Chromium (II) oxide (III) c) Chromium trioxide d) Trichromium dioxide 46. In the periodic table, the elements are arranged in order of increasing... a) Number of neutrons b) Number of protons c) Ionization energy d) Electronegativity 47. Which molecule shows covalent bonding, with the least ionic character? a) F-Be-F b) F-Li c) F-Br d) F-F 5
48. Which pair of characteristics applies to typical ionic solids? a) Good electrical conductivity and high ionization energy b) High melting point and malleability c) High melting point and crystalline structure d) Low melting point and low aqueous solubility 49. The following electronic configuration applies to a neutral atom or a cation: The element or ion could be: 1s 2 2s 2 2p 6 3s 2 3p 6 4s 1 a) An argon ion b) A neutral potassium atom c) A chloride ion d) A neutral calcium atom 50. Sulfur has three natural isotopes of relative masses 32.0, 33.0, 34.0. If the relative atomic mass of sulfur is 32.07, which one of the following statements must be correct? a) 32 S is less abundant than 34 S b) 34 S is more abundant than 33 S c) 32 S is more abundant than either 33 S or 34 S d) Another natural isotope of lesser mass must exist 51. Which of the following compounds possesses at least one σ bond: A. CH 4 B. C 2 H 2 C. C 2 H 4 D. All of the above 52. In a double-bonded carbon atom: A. hybridization between the s orbital and one p orbital occurs. B. hybridization between the s orbital and two p orbital occurs. C. hybridization between the s orbital and three p orbital occurs. D. no hybridization occurs between the s and p orbitals. 53. Which of the following hybridizations does the Be atom in BeH 2 assume? A. sp B. sp 2 C. sp 3 D. None of the above 54. π bonds are formed by which of the following orbitals? A. two s orbitals B. two p orbitals C. one s and one p orbital D. All of the above 55. Which of the following decrease(s) as the number of bonds between two atoms increases? I. Bond length II. Bond strength A. I only B. II only C. Both I and II D. Neither I nor II 56. What type of hybrid orbitals are used for bonding by Xe in the XeF 4 molecule? A. sp 2 B. sp 3 C. dsp 3 D. d 2 sp 3 57. The hybridization of the carbon atom in the carbonate ion, CO 3 2-, is best described as : A. sp B. sp 2 C. sp 3 D. sp 3 d 2 6
58. The following equations represent processes in which solid calcium fluoride is formed. Which one of these has an enthalpy change which is known as the lattice energy of calcium fluoride? A. Ca (s) + F 2 (g) sssssd CaF 2 (s) B. Ca (g) + 2F (g) sssssd CaF 2 (s) C. Ca 2+ (g) + 2F - (g) sssssd CaF 2 (s) D. Ca 2+ (s) + 2F - (g) sssssd CaF 2 (s) 59. Which one of the following compounds would be expected to have the highest crystal lattice energy? A. MgS B. MgO C. CaSO 4 D. BaSO 4 60. Which one of the following species would be deflected by an electric field? I-electron II-proton III-neutron A. I only B. III only C. I and II only D. I, II, and III Answers : Exam Review: Multiple Choice 1 2 3 4 5 6 7 8 9 10 A A D B A A C D B B 11 12 13 14 15 16 17 18 19 20 C A B A B A C A D D 21 22 23 24 25 26 27 28 29 30 B C C C C C B D D B 31 32 33 34 35 36 37 38 39 40 A B C A D C D D A C 41 42 43 44 45 46 47 48 49 50 A B D D A B D C B C 51 52 53 54 55 56 57 58 59 60 D B A B A D B C B C 7
Exam Review II 1. What amount of oxygen, O 2, (in moles) contains 1.8 10 22 molecules? A. 0.0030 B. 0.030 C. 0.30 D. 3.0 2. A hydrocarbon contains 90% by mass of carbon. What is its empirical formula? A. CH 2 B. C 3 H 4 C. C 7 H 10 D. C 9 H 10 3. 6.0 moles of Fe 2 O 3 (s) reacts with 9.0 moles of carbon in a blast furnace according to the equation below. Fe 2 O 3 (s) + 3C(s) sssssd 2Fe(s) + 3CO(g) What is the limiting reagent and hence the theoretical yield of iron? Limiting reagent Theoretical yield of iron A. Fe 2 O 3 6.0 mol B. Fe 2 O 3 12.0 mol C. carbon 9.0 mol D. carbon 6.0 mol 4. Calcium carbonate decomposes on heating as shown below. CaCO 3 sssssd CaO + CO 2 When 50 g of calcium carbonate are decomposed, 7 g of calcium oxide are formed. What is the percentage yield of calcium oxide? A. 7% B. 25% C. 50% D. 75% 5. What amount of NaCl (in moles) is required to prepare 250 cm 3 of a 0.200 mol dm 3 solution? A. 50.0 B. 1.25 C. 0.800 D. 0.0500 6. What volume, in cm 3, of 0.200 mol dm 3 HCl (aq) is required to neutralize 25.0 cm 3 of 0.200 mol dm 3 Ba(OH) 2 (aq)? A. 12.5 B. 25.0 C. 50.0 D. 75.0 7. Which change in conditions would increase the volume of a fixed mass of gas? Pressure /kpa Temperature /K A. Doubled Doubled B. Halved Halved C. Doubled Halved D. Halved Doubled 8
8. The temperature in Kelvin of 2.0 dm 3 of an ideal gas is doubled and its pressure is increased by a factor of four. What is the final volume of the gas? A. 1.0 dm 3 B. 2.0 dm 3 C. 3.0 dm 3 D. 4.0 dm 3 9. Consider the following reaction: N 2 (g) + 3H 2 (g) qwwwwe 2 NH 3 (g) If the reaction is made to go to completion, what volume of ammonia (in dm 3 ) can be prepared from 25 dm 3 of nitrogen and 60 dm 3 of hydrogen? All volumes are measured at the same temperature and pressure. A. 40 B. 50 C. 85 D. 120 10. Ethyne, C 2 H 2, reacts with oxygen according to the equation below. What volume of oxygen (in dm 3 ) reacts with 0.40 dm 3 of C 2 H 2? 2C 2 H 2 (g) + 5O 2 (g) sssssd 4CO 2 (g) + 2H 2 O(g) A. 0.40 B. 0.80 C. 1.0 D. 2.0 11. Which one of the following species can act as both a Brønsted-Lowry acid and base in aqueous solution? A. CH 3 COOH B. NO 3 C. H 2 PO 4 12. Which is a conjugate acid-base pair in the following reaction? HNO 3 + H 2 SO 4 qwwwwe H 2 NO 3 + + HSO 4 A. HNO 3 and H 2 SO 4 B. HNO 3 and H 2 NO 3 + C. HNO 3 and HSO 4 D. H 2 NO 3 + and HSO 4 D. OH 13. Which equation represents an acid-base reaction according to the Lewis theory but not according to the Brønsted-Lowry theory? A. CO 3 2 (aq) + 2H + (aq) H 2 O(l) + CO 2 (g) B. Cu 2+ (aq) + 4NH 3 (aq) CU(NH 3 ) 4 2+ (aq) C. BaO(s) + H 2 O(l) Ba 2+ (aq) + 2OH (aq) D. NH 3 (g) + HCl(g) NH 4 Cl(s) 9
14. Which methods can distinguish between solutions of a strong monoprotic acid and a weak monoprotic acid of the same concentration? I. Add magnesium to each solution and measure the rate of the formation of gas bubbles. II. Add aqueous sodium hydroxide to each solution and measure the temperature change. III. Use each solution in a circuit with a battery and lamp and see how bright the lamp glows. A. I and II only B. I and III only C. II and III only D. I, II and III 15. Solutions of hydrochloric acid (HCl(aq)) and ethanoic acid (CH 3 COOH(aq)) of the same concentration reacted completely with 5.0 g of calcium carbonate in separate containers. Which statement is correct? A. CH 3 COOH(aq) reacted slower because it has a lower ph than HCl(aq). B. A smaller volume of CO 2 (g) was produced with CH 3 COOH(aq) than with HCl(aq). C. A greater volume of CO 2 (g) was produced with CH 3 COOH(aq) than with HCl(aq). D. The same volume of CO 2 (g) was produced with both CH 3 COOH(aq) and HCl(aq). 16. What is the conjugate base of the HSO 4 (aq) ion? A. H 2 SO 4 (aq) B. SO 4 2 (aq) C. H 2 O(l) D. H 3 O + (aq) 17. What is the number of sigma (σ) and pi (π) bonds and the hybridization of the carbon atom in : O H C O H Sigma Pi Hybridization A. 4 1 sp 2 B. 4 1 sp 3 C. 3 2 sp 3 D. 3 1 sp 2 18. Which of the following increase(s) for the bonding between carbon atoms in the sequence of molecules C 2 H 6, C 2 H 4 and C 2 H 2? I. Number of bonds II. Length of bonds III. Strength of bonding A. I only B. I and III only C. III only D. I, II and III 10
19. Which allotropes contain carbon atoms with sp 2 hybridization? I. Diamond II. Graphite III. C 60 fullerene A. I and II only B. I and III only C. II and III only D. I, II and II 20. What is the molecular shape and the hybridization of the nitrogen atom in NH 3? Molecular shape Hybridization A. tetrahedral sp 3 B. trigonal planar sp 2 C. trigonal pyramidal sp 2 D. trigonal pyramidal sp 3 21. Which substance has the lowest electrical conductivity? A. Cu(s) B. Hg(l) C. H 2 (g) D. LiOH(aq) 22. Which statement is correct about multiple bonding between carbon atoms? A. Double bonds are formed by two π bonds. B. Double bonds are weaker than single bonds. C. π bonds are formed by overlap between s orbitals. D. π bonds are weaker than sigma bonds. 23. Which particles can act as ligands in complex ion formation? I. C1 II. NH 3 III. H 2 O A. I and II only B. I and III only C. II and III only D. I, II and III 24. Which statements correctly describe the NO 2 ion? I. It can be represented by resonance structures. II. III. It has two lone pairs of electrons on the N atom. The N atom is sp 2 hybridized. A. I and II only B. I and III only C. II and III only D. I, II and III 25. In which substance is hydrogen bonding present? A. CH 4 B. CH 2 F 2 C. CH 3 CHO D. CH 3 OH 11
26. Which types of hybridization are shown by the carbon atoms in the compound CH 2 = CH CH 3? I. sp II. sp 2 III. sp 3 A. I and II only B. I and III only C. II and III only D. I, II and III 27. Identify the types of hybridization shown by the carbon atoms in the molecule CH 3 CH 2 CH 2 COOH I. sp II. sp 2 III. sp 3 A. I and II only B. I and III only C. II and III only D. I, II and III 28. When C 2 H 4, C 2 H 2 and C 2 H 6 are arranged in order of increasing C C bond length, what is the correct order? A. C 2 H 6, C 2 H 2, C 2 H 4 B. C 2 H 4, C 2 H 2, C 2 H 6 C. C 2 H 2, C 2 H 4, C 2 H 6 D. C 2 H 4, C 2 H 6, C 2 H 2 29. What is the molecular geometry and the Cl I Cl bond angle in the ICl 4 ion? A. Square planar 90 B. Square pyramidal 90 C. Tetrahedral 109 D. Trigonal pyramidal 107 30. How many sigma (σ) and pi (π) bonds are present in the structure of HCN? σ π A. 1 3 B. 2 3 C. 2 2 D. 3 1 Answers: Exam Review II 1 2 3 4 5 6 7 8 9 10 B B D B D C D A A C 11 12 13 14 15 16 17 18 19 20 C B B D D B A B C D 21 22 23 24 25 26 27 28 29 30 C D D B D C C C A C 12